You might hope that this kind of behaviour is a relatively rare phenomenon, restricted to a few extreme situations. But self-deception is incredibly common, and may have evolved to bring some personal benefits. We lie to ourselves to protect our self-images, which allows us to act immorally while maintaining a clear conscience. According to the very latest research, self-deception may have even evolved to help us to persuade others; if we start believing our own lies, it’s much easier to get other people to believe them, too.
